In an electronic data storage and retrieval system, a transducing head typically includes a writer for storing magnetically-encoded information on a magnetic disc and a reader for retrieving that magnetically encoded information from the magnetic disc. For a perpendicular recording head, the writer portion typically includes a main (or write element) pole and a return pole, which are separated from each other at a medium confronting surface of the writer by a gap layer, and which are connected to each other at a region distal from the air bearing surface by a back gap closer or back via. One or more layers of conductive coils are positioned between the main and return poles, and are encapsulated by insulating layers.
To write data to the magnetic media, an electric current is caused to flow through the conductive coils to induce a magnetic field across the write gap between the main and return poles. By reversing the direction of the current through the coils, the polarity of the data written to the magnetic media is reversed. In perpendicular recording, magnetic signals are conducted through the main pole in a manner that orients the magnetic moments of the recording medium perpendicularly to the surface of the recording medium. The amount of data that can be recorded in a given area (i.e., the areal density) can be improved by reducing the surface area of the pole tip of the writing pole and by increasing the linear density and the frequency at which data is recorded.
One issue confronting some magnetic writers is the occurrence of unwanted erasure of portions of the magnetic medium following a write operation. This has been attributed to the remnant domain state of the write element. More particularly, the desirable easy axis remnant domain configuration in the write element is significantly degraded when the write element is magnetized along the hard axis, which occurs during the write operation. One approach to resolving this issue is to laminate magnetic layers of the write element with nonmagnetic layers. However, because the laminating layers are nonmagnetic, this approach results in a decrease of the effective moment of the write element, which decreases the ability of the write field to overcome the coercivity of the magnetic medium.